Conciseness

The body is mostly efficient with real API examples, but includes unnecessary padding: the "Purpose" section restates the frontmatter description almost verbatim, and comments/details like "# Improve code structure" and the RED/GREEN/REFACTOR detail lists re-explain standard TDD practice Claude already knows. This fits score 3 ('some unnecessary explanation or could be tightened') better than score 4, since the redundancy spans more than minor instances.

Actionability

Quick Start and phase snippets are executable and match the actual script (TDDRunner, run_cycle, red/green/refactor_phase all verified in scripts/tdd_runner.py), and the Cycle Result JSON documents the concrete output shape. Minor gaps remain — how the `feature` dict is constructed, where `project_dir` points, and how the Configuration JSON is loaded — so it stops short of fully copy-paste-ready coverage of the common cases (score 5).

Workflow Clarity

The TDD Cycle section sequences all three phases with code, and each phase's details include explicit validation and feedback loops: "If tests pass unexpectedly, add more specific assertions", "If tests fail, iterate on implementation. Stop when all tests pass", and "Run tests after each change. Revert if tests fail". This matches the score-5 anchor (clear sequence, explicit validation, error-recovery loops), including a revert-on-failure rollback.

Progressive Disclosure

Good structure: key runnable examples are inline, and the bulk implementation is one level deep in scripts/tdd_runner.py, clearly signaled by "See scripts/tdd_runner.py for full implementation" (the file and its symbols exist). It is not score 5 because the inlined Cycle Result schema and Configuration block are API details that could live in a separate reference file, and the API Reference section is a bare pointer with no key examples inline — minor organization gaps matching score 4.

Specificity

"Run TDD cycle for feature implementation" names the domain and a single concrete action (running the RED-GREEN-REFACTOR cycle), but does not list several specific actions like creating failing tests, iterating implementations, or refactoring — matching the '1-2 concrete actions, not comprehensive' anchor. It exceeds score 2 because the action is domain-specific rather than generic, but falls short of score 4's 'several specific actions' with only one action stated.

Completeness

The 'what' is explicit ("Run TDD cycle for feature implementation") and the 'when' is explicit with concrete trigger phrases ("Use when implementing features with RED-GREEN-REFACTOR, running test-driven development, automating TDD workflow, or ensuring test-first development"). Both parts are clearly and concretely answered, matching the score-5 anchor; score 4 would require the 'when' to be less explicit than it is.

Trigger Term Quality

"running test-driven development", "automating TDD workflow", "ensuring test-first development", and "RED-GREEN-REFACTOR" are natural phrases a user would say when needing this skill. A few common variations are missing (e.g., "write failing tests first", "test-first coding"), so it does not reach the comprehensive synonym coverage of score 5, but it clearly exceeds the partial coverage of score 3.

Distinctiveness Conflict Risk

The TDD/test-first niche with RED-GREEN-REFACTOR triggers is mostly distinct from other skills, but "implementing features" is broad and could overlap with generic test-generation or feature-implementation skills. Minor overlap risk with closely related skills fits score 4 rather than score 5's 'minimal conflict risk'.